1 Introduction

1.1 Background

This document provides a detailed summary of remote emission sensing (RES) data as part of the CARES project.

1.2 Aims

The analysis of RES data can be challenging given the complexity and typical size of the data collected during experimental campaigns. Even within the small community of researchers and practitioners that typically conduct experiments, there is a wide variation in the analysis approaches used and their consistency. With that in mind, this document has the following aims:

  1. To provide a reliable and automated way of presenting key summary data and plots from RES campaigns.

  2. Adopt ‘modern’ data analysis approaches using R Statistical Software and automated report production using Rmarkdown.

  3. These approaches offer many advantages over traditional ways of analysing data and presenting it. For example, allowing for detailed data to be presented in a compact way that can easily be filtered by the user, and the use of ‘tabs’ to better structure the output.

  4. To present common numerical and graphical outputs that help to interpret data from RES campaigns.

The analysis software and the underlying code that produced this document are part of a R package called openCARES. The package is available as a GitHub repository and all code is managed under a version control system. The approach means that all changes are recorded and that members of the CARES team can work collaboratively to develop the analysis capabilities over time.

Currently, this document is based on early data collected as part of the CONOX project consisting of about 100,000 measurements, which is similar to the aims of the City Demonstrations as part of the CARES project.

2 Vehicle numbers

This section focuses on the share of measurements per vehicle class, fuel type, Euro standard and so on.

2.1 Vehicle and fuel type

An example of a way in which to present vehicles samples is shown in Figure 2.1.

Figure 2.1: Numbers of vehicle by main vehicle and fuel type. Click on the key to select specific segments.

2.2 Euro standard

Euro standard share by main vehicle and fuel type.

Figure 2.2: Euro standard share by main vehicle and fuel type.

2.3 Manufacturers

Manufacturer composition for petrol and diesel vehicles. The size of each rectangle is proportional to the share of each manufacturer / manufacturer group.

2.3.1 Petrol vehicles

2.3.2 Diesel vehicles

3 Site conditions

Road grade etc.

4 Environmental conditions

4.1 Meteorological data

4.1.1 All data

4.1.2 By site

4.2 Emissions as a function of ambient temperature

5 Vehicle emissions

5.1 Average emissions by Euro standard

5.1.1 CO

5.2 Average emissions by model year

5.2.1 CO

5.3 Average emissions by manufacturer

5.3.1 PC gasoline

5.4 Average emissions by engine size

5.5 Emission summaries

All data presented as fuel-specific emission factors i.e. g pollutant per kg fuel.

5.5.1 All data

NOx NO CO HC UV_smoke n
15.83 12.80 12.07 4.34 NaN 100.00K

5.5.2 By fuel

FuelType NOx NO CO HC UV_smoke n
BATTERY ELECTRIC NaN 2.65 2.41 −2.61 NaN 1.00
BIFUEL LPG/PETROL NaN 10.34 115.35 7.92 NaN 33.00
DIESEL 20.90 16.82 3.50 3.52 NaN 63.61K
HYBRID DIESEL/ELECTRIC 13.61 13.24 2.02 1.72 NaN 105.00
HYBRID PETROL/ELECTRIC 1.56 1.33 8.20 3.81 NaN 879.00
NO DATA 7.73 7.35 40.87 7.71 NaN 469.00
PETROL 5.78 5.84 27.33 5.81 NaN 34.91K

5.6 Detailed pollutant summaries

5.6.1 NOx

The table below shows the mean and 95% confidence interval in the mean is given.

5.6.2 CO

The table below shows the mean and 95% confidence interval in the mean is given.

5.6.3 HC

The table below shows the mean and 95% confidence interval in the mean is given.

5.6.4 UV smoke

The table below shows the mean and 95% confidence interval in the mean is given.

6 Vehicle dynamics

Speed, acceleration, VSP.

6.1 Measurement conditions

6.1.1 All data

Speed (kph) VSP n
36.28 4.88 80.92K
Density plot of all VSP data.

Figure 6.1: Density plot of all VSP data.

6.1.2 By site

Site Speed (kph) VSP n
A40 60.14 5.37 8.60K
Aldersgate 28.27 3.77 6.45K
Cambridge 32.33 5.92 3.48K
Greenford 40.79 2.83 15.24K
Queen Victoria 30.66 4.41 18.74K
Sheffield 32.66 6.26 28.41K
Density plot of all VSP data, split by site.

Figure 6.2: Density plot of all VSP data, split by site.

7 Deterioration effects

Average emissions by vehicle age + mileage.

8 Distance specific emissions

See conox_gkm.R